1. Field of the Invention
The present invention relates to a measuring device that measures a measuring object.
2. Description of Related Art
In a measuring device of a triangular distance measuring method, a surface of a measuring object is irradiated with light, and a light receiving element including pixels arrayed one-dimensionally or two-dimensionally receives the light reflected from the surface. A height of the surface of the measuring object can be measured based on a peak position of a light reception amount distribution obtained by the light receiving element.
Shape measurement of the triangular distance measuring method in which coded light and a phase shift method are combined is proposed in Toni F. Schenk, “Remote Sensing and Reconstruction for Three-Dimensional Objects and Scenes”, Proceedings of SPIE, Volume 2572, pp. 1-9 (1995).
Shape measurement of the triangular distance measuring method in which coded light and stripe light are combined is proposed in Sabry F. El-Hakim and Armin Gruen, “Videometrics and Optical Methods for 3D Shape Measurement”, Proceedings of SPIE, Volume 4309, pp. 219-231 (2001). In these methods, shape measurement accuracy of the measuring object can be improved.
As described above, in the shape measurement of the triangular distance measuring method, the surface of the measuring object is irradiated with light in order to measure the shape. At this time, usually the measuring object and a space including a periphery of the measuring object are irradiated with the light used in the measurement. Therefore, part of the measurement light is reflected by the surface of the measuring object, and received by the light receiving element. On the other hand, the remaining of the measurement light is reflected by a placement surface on which the measuring object is placed and a surface of a member provided in a periphery of the placement surface, and received by the light receiving element.
In such cases, data obtained by the shape measurement of the triangular distance measuring method includes unnecessary data indicating the shape of the member other than the measuring object. There is a possibility that the shape of the measuring object is mistakenly measured due to existence of the unnecessary data. A method for removing the unnecessary data from the obtained data is conceivable in order to prevent the measurement error. However, the processing is troublesome, and demands skill and experience.